The present invention relates to zippered bags, and more particularly, to an end seal used in connection with such bags. It is known to use airtight plastic bags and containers to conveniently store bulky materials such as clothing and bedding. Airtight plastic bags are also known to store food and other materials. Examples of such airtight bags are disclosed in U.S. Pat. Nos. 6,357,915; 6,116,781; and 5,480,030, each of which is incorporated herein by reference. Airtight bags allow air to be removed from bulky items such as comforters and sweaters, and the bag sealed to essentially “shrink” the items stored inside the bag. Air can be compressed from the contents, for example, by rolling the contents prior to closing the bag. The bags may also have a one-way valve to which a vacuum attachment can be affixed to evacuate the air from inside the bag using a conventional household vacuum cleaner. Removal of air reduces the amount of space necessary to store the items. When food items are stored, air can be squeezed from the bag prior to closing. The bags are typically made of materials such as bi-axial layers of nylon and polyethylene to make the bags air and moisture impermeable, and hold the airtight vacuum seal.
The bags have a zippered closure at the mouth of the bag. An example of a zippered closure is disclosed in U.S. Pat. No. 6,033,113, incorporated herein by reference. The zippered closure is typically made of plastic. Often associated with the zippered closure is a slider that facilitates sealing the zippered closure. The slider closes and can open the zippered closure. Examples of sliders include those disclosed in U.S. Pat. Nos. 6,306,071; 6,287,001; 6,264,366; 6,247,844; 5,950,285; 5,924,173; 5,836,056; 5,442,837; 5,161,286; 5,131,121; 5,088,971; and 5,067,208.
It is well known in the art of bagmaking to crush the ends of the zippered closures. The bags are longitudinally cut at the crushed sections or “end stomps” to create separate bags which typically are formed in a continuous web. When the zippered closure ends are crushed, the zippered closure is melted and deformed in such areas. Incorrect or incomplete crushing results in voids in the transition zone between the end stomp and the intact zipper profile through which air can travel. Thus, the bags will not be airtight.